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Background: Combat sports, including MMA and BJJ place very high and varied demands on athletes in terms of strength and strength-endurance training. The aim of the present study was to level of development motor fitness athletes combat sports and examine their relationship with training experience, and high sports performance. Methods: Thirty athletes were studied and compared between two groups: MMA (N=15) and BJJ (N=15). Somatic measurements were performed. Selected manifestations of the athletes potential in terms of strength and strength endurance were also measured, using selected tests from the International Physical Fitness Test (EUROFIT) battery, and relative strength and MAW indices were calculated. A coach ranking of athletes by sports achievement was developed. Next, the strength of the relationship of the effect of the aspects of strength and conditioning with training experience and sports performance was assessed. Results: The level of motor fitness in the groups was significantly different between the athletes of these sports in terms of strength and strength endurance abilities (p=0,006-0,038). A higher level of these elements of fitness was displayed by BJJ athletes. In both groups, significant correlations were found between the motor effect and the training experience (r=0,53-0,89) also sports result (r=0,53-0,76). Conclusions: The results allow for the initial diagnosis and interpretation of motor fitness competencies along with the profile of its key manifestations in MMA and BJJ, which promotes optimization of the quality of coaching control.

Aims The coronavirus disease‐2019 (COVID‐19) pandemic has changed the landscape of medical care delivery worldwide. We aimed to assess the influence of COVID‐19 pandemic on hospital admissions and in‐hospital mortality rate in patients with acute heart failure (AHF) in a retrospective, multicentre study. Methods and results From 1 January 2019 to 31 December 2020, a total of 101 433 patients were hospitalized in 24 Cardiology Departments in Poland. The number of patients admitted due to AHF decreased by 23.4% from 9853 in 2019 to 7546 in 2020 (P

The aim of this study was to examine novel putative markers of the response to the competitive soccer match in adolescent players, such as changes in global levels of γH2AX and H4K16ac in the chromatin of peripheral mononuclear blood cells (PMBCs) and a Fourier-transform infrared spectroscopy (FTIR)-based biochemical fingerprint of serum. These characteristics were examined with reference to the physiological and metabolic aspects of this response. Immediately post-match we noticed: (1) a systemic inflammatory response, manifesting as peaks in leukocyte count and changes in concentrations of IL-6, TNFα, and cortisol; (2) a peak in plasma lactate; (3) onset of oxidative stress, manifesting as a decline in GSH/GSSG; (4) onset of muscle injury, reflected in an increase in CK activity. Twenty-four hours post-match the decrease in GSH/GSSG was accompanied by accumulation of MDA and 8-OHdG, macromolecule oxidation end-products, and an increase in CK activity. No changes in SOD1 or GPX1 levels were found. Repeated measures correlation revealed several associations between the investigated biomarkers. The FTIR analysis revealed that the match had the greatest impact on serum lipid profile immediately post-game. In turn, increases in γH2AX and H4K16ac levels at 24 h post-match indicated activation of a DNA repair pathway.

We nowadays record growing numbers of e-cigarette users. The development of nicotine dependence is a result of many factors, including genetics and personality. In this study we analyzed two polymorphisms-rs1985242 and rs1062613-in the serotonin receptor

Background: Blood tests are a common health assessment for diagnosing diseases and bodily disorders. Aims: The aim of the work was to analyze the suitability of sampling and assessing athletes’ blood-borne biomarkers in a search for ways to optimize their football training. Methods: In the prospective study, the results of 14 football players from a youth football team competing at the highest national level ‘blood tests were evaluated before (P1), immediately after (P2) and 24 hours after (P3) playing a football match. The all players were divided into two groups based on the length of time they were on the field during the game: FMP - (8 players) participation in the match for 90 minutes, and PMP - (6 players) participation in the match for 30-75 minutes. Results: In the FMP group, at P2, the following statistically significant (p

Cortisol is a stress hormone that plays a crucial role in the balance between phospholipids and lipids levels. In consequence, it affects the secondary structure of proteins. Currently cortisol concentration in serum is determined by a biochemical analysis. A new optical method to estimate the stress level is proposed in this work. Infrared and Raman spectroscopies were used to determine the quantitative and qualitative changes in lipids and proteins fractions in the function of cortisol concentration in 49 samples of serum collected from volleyball players at various stages of preparation for the competition. With the cortisol level increase, a decrease of structures related to PO2- phospholipid groups and amides III and I bonds was noticed in the Raman spectra. The differences in absorbance visible in the FTIR spectra, were not statistically significant. However, the calculated absorbance ratios between the peaks related to vibrations of the lipid functional groups and amide I show, that with the increase of cortisol concentration, the increase of the amount of lipids and the decrease of the amount of proteins was observed in transmission spectra. Pearson correlation test presented positive correlations between phospholipid and protein levels and between cortisol concentration and phospholipids in transmittance spectra. Negative correlations between cortisol concentration, protein and phospholipid levels were observed in the Raman spectra. Obtained results showed, that using Raman spectroscopy the effect of increased cortisol concentration on proteins, phospholipids and lipids is directly visible. in the case of FTIR spectroscopy, one had to calculate the ratios between CH2 and CH3 lipids vibrations (2957 cm-1, 2920 cm-1, 2872 cm-1) and amide I (1654 cm-1), to show differences in the cortisol concentration in serum. These results suggest, that Raman spectroscopy is a more promising technique to obtain an information about cortisol levels in serum.

Background Due to the high postural control demands of sport ju-jitsu, it is likely that long-term sport ju-jitsu training may induce sport-specific adaptations in postural control, especially in positions directly related to combat. The aim of the study was to assess the differences in postural control between elite sport ju-jitsu athletes and untrained controls in non-ecological and ecological conditions and to investigate the relative contribution of spinal and supraspinal mechanisms to postural control in expert athletes. Methods The study was conducted on eleven male elite ju-jitsu athletes and ten non-athletes. The data was collected with the use of a force plate under two conditions: quiet standing and ju-jitsu combat stance. Apart from the standard analysis of the spatial–temporal parameters of center of foot pressure, non-linear measures were used, namely rambling-trembling and sample entropy. The non-parametric Mann–Whitney U test was used to compare both groups. Results The main findings of the study showed that in quiet standing, elite ju-jitsu athletes and non-athletes had comparable postural control in both the anterior–posterior and mediolateral planes. In contrast, in the combat stance, elite athletes had lower values of postural sway and rambling component (range and rms) and higher values of sample entropy in comparison to the non-athletes (p p Conclusions Smaller postural sway and its rambling component in sport ju-jitsu athletes may indicate the more precise control of center of foot pressure and improved ability in estimating its position. The sample entropy results confirmed that the displacement of center of foot pressure for sport ju-jitsu athletes was more irregular, which demonstrates greater automatization in postural control. The results also confirm the importance of ecological validity in investigating postural adaptations associated with sports expertise.

Background The work of teachers during the COVID-19 pandemic created additional challenges and required them to go beyond conventional teaching methods, which in turn required teachers to be more resilient and caused stress and excessive workload. The aim of the study was to assess the level of occupational burnout, the sense of job satisfaction and the self-efficacy of primary and secondary school teachers working during the COVID-19 pandemic in Poland. Methods This is a cross-sectional descriptive study conducted among 412 teachers from randomly selected primary and secondary schools in the Podkarpacie region in Poland. The questionnaire contained socio-demographic data of the respondents and three standardized scales: The Scale of Job Satisfaction (SJS), General Self-Efficacy Scale (GSES) and Arbeitsbesorgenes Verhaltens und Erlebenmuster (AVEM). The Shapiro–Wilk, Kruskal–Wallis and Mann–Whitney U-test were used. Statistical analysis was performed with Statistica TIBCO 13.3 and R (version 3.6.1) software. Results The satisfaction with the work of the surveyed teachers was average in the job satisfaction scale. The vast majority of the surveyed teachers presented type B (overburdened risk type) of work-related behavior, and type A (overburdened risk type) in which the probability of burnout is very high. The feeling of self-effectiveness determines the level of job satisfaction and the level of professional burnout among the surveyed teachers. Job satisfaction had a statistically significant impact on the assessment of self-efficacy of the surveyed teachers (p p Conclusion There is a close relationship between teachers’ level of self- efficacy, job satisfaction and, therefore it may predispose them to the occurrence of burnout syndrome in the future. Support for this professional group is needed. These findings may be important for education policy, teacher’s practice, and subsequent research. Ultimately, the study may provide some suggestions for methodological and educational strategies.

Background: The testing of athletes in ecological conditions is based on the concept that sport-specific adaptations in postural control are observed mostly in positions or tasks that are related to the practice of a specific movement. Due to the high postural control demands of ju-jitsu, it is likely that long-term ju-jitsu training may influence the process of maintaining a stable posture, especially in positions directly related to combat. The purpose of this study was to examine the postural sway characteristics of elite ju-jitsu athletes in ecological and non-ecological conditions with an approach not previously used in martial arts.Methods: The study was conducted on eleven male elite ju-jitsu athletes and ten non-athletes. The data was collected with the use of a force plate under two conditions: quiet standing and ju-jitsu combat stance. Apart from the standard analysis of the spatial-temporal parameters of COP, sensitive methods in COP data processing were used, namely rambling-trembling and sample entropy. The non-parametric U Mann-Whitney test was used to compare both positions.Results: The main findings of the study showed that in quiet standing, elite ju-jitsu athletes and non-athletes had comparable postural control in both the anterior-posterior and mediolateral planes. In contrast, elite athletes had lower values of postural sway and higher values of sample entropy in comparison to the non-trainees in the combat stance (pConclusions: Our results confirmed the importance of a sport-specific environment in investigating the subtle differences in the postural regulation of elite athletes. The sample entropy results indicated more irregular characteristics of postural sway in the elite ju-jitsu athletes, representing more automated postural control.

This paper presents results of a research on the effect of a high temperature, resulting from the storage technology, on the utilization level of stresses in selected individual structural components of a cylindrical, above-ground steel tank with a vertical axis and a fixed roof. Computational simulations were performed for the geometry of an existing facility that had failed during the service life. The analyses conducted resulted in specifying members, in the case of which taking into account thermal effects in the dimensioning process is desirable, undesirable or negligible from the point of view of operational safety.

The analysis and evaluation of cracks in three different case studies of glued laminated timber structures is presented in the paper. The analysis is performed from the point of view of possible failure due to crack defects.

The level of physical activity is conditioned by many different factors, including, among others, the personality traits of a person. Important is the fact that personality traits are a moderately heritable factor and on the basis of the analysis of several genes, various lifetime outcomes can be predicted. One of the most important pathways influencing personality traits is connected to the dopaminergic system, hence, we decided to analyze the DRD2&nbsp, PROM. rs1799732, DRD2 rs1076560, DRD2 Tag1D rs1800498, DRD2 Ex8 rs6276, DRD2Tag1B rs1079597 and ANKK1 Tag1A rs180049. The research group included 258 male athletes (mean age = 26.02, SD = 8.30), whereas the control group was 284 healthy male volunteers matched for age (mean age = 22.89, SD = 4.78), both of Caucasian origin and without history of substance dependency or psychosis. Genomic DNA was extracted from venous blood using standard procedures. Genotyping was conducted with the real-time PCR method. Differences in the frequency of the DRD2Tag1B rs1079597 gene polymorphism were found between people practicing combat sports and the control group, and the DRD2 PROM. rs1799732, DRD2 rs1076560, DRD2 Tag1D rs1800498, DRD2 Ex8 rs6276, DRD2Tag1B rs1079597 and ANKK1 Tag1A rs1800497 genotypes and allele frequencies in the studied sample did not differ between the analyzed groups. Hence, we considered these polymorphic places as an interesting area for the further search for unambiguous associations between personality traits and attitude towards physical effort.

The article presents results of research consisting in an attempt to assess the influence of temperature, heating time and cooling method on microstructure and residual strength properties of steel previously tempered during the production process. Simulated environmental conditions to which high-strength bolts, commonly used in steel construction, were subjected, were intended to reflect conditions of a natural fire that may occur in public facilities where the obligation to ensure safety of users and rescue teams is of key importance, also required by law. Furthermore, the tests carried out also comprised a simulated effect of a rescue and firefighting operation using shock, rapid cooling of some of the heated bolts. Samples cut out from the tested bolts, after they were properly prepared, were subjected to microstructural tests using light microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), phase analysis with the use of an X-ray diffractometer (XRD) and quantitative analysis of the microstructure involving, inter alia, measuring the surface area of grains, their equivalent diameter and mean diameter. As a result of the tests, considerable microstructure changes were identified occurring in the bolt material as a result of exposing it to fire conditions, leading to a change in key, from the point of view of structural safety, mechanical properties. The results of the microstructure tests were compared with the results of previous strength tests, including hardness of the material after the heat treatment and the residual tensile strength of the material Rm. A conducted comparative analysis showed a significant effect of all such factors as the temperature level of the simulated fire, its duration and the fire-fighting method on the mechanical properties of bolts. Results obtained were provided with required comments and the concept of using the microstructure for the post-fire assessment of steel structures was referred to.

Physical activity is one of the factors conditioning human health. Research shows a positive impact of regular physical activity on the quality of human life. The aim of the study was to determine the relationship between the physical activity of university students, their parents, and their grandparents, and the overall quality of their lives in individual domains (physical, mental, social, environmental), as well as the perceived state of health in relation to selected determinants. The research included 1001 participants, including 253 students related to physical culture and health promotion studying at the University of Szczecin (faculties: physical education, tourism and recreation, public health, sports diagnostics), and their 336 parents and 412 grandparents. Purposive sampling was used to outline the determinants of quality of life and family factors in physical activity. The diagnostic survey was carried out based on the standardized WHOQOL-BREF (World Health Organization Quality of Life) questionnaire. Statistically significant differences were shown in the studied generations regarding the assessment of quality of life and satisfaction with health in the physical, psychological, social, and environmental domains. The oldest generation gave the lowest assessment of quality of life and was the least satisfied with their health regarding particular domains. Female students were more satisfied with their health compared to grandmothers and grandfathers, whereas male students compared to mothers and fathers. Fathers achieved the highest scores in the psychological and social domains, but, in case of the latter, differences were found between mothers’ and fathers’ assessments. Intergenerational differences were found in quality of life and the assessment of health status. Current participation in broadly understood physical culture was often a result of positive attitudes towards physical education and doing sport in the past, which meant higher scores in the physical domain each time. The study demonstrated that taking up physical activity impacted the quality of life and assessment of health in the past and currently.

Cortisol is a stress hormone plays a crucial role in the balance between phospholipids and lipids level. In consequence, it affects the secondary structure of proteins. Currently cortisol concentration in plasma is determined by biochemical analysis. A new, optical method to estimate stress level is proposed in this work. Infrared and Raman spectroscopies were used to determine quantitative and qualitative changes in the lipids and proteins fraction in function of cortisol concentration in 49 samples of plasma collected from volleyball players at various stages of preparation for the competition. With the cortisol level increase, a decrease of structures related to PO2- phospholipids groups and amides III, II and I bonds was noticed in the transmission spectra. Changes in the secondary structure of protein were indicated as a frequency shift of α-helix and β-sheet vibrations observed in Raman spectra and second derivative of transmission spectra. Pearson correlation test presented positive correlations between phospholipids and proteins level and between cortisol concentration and phospholipids in transmittance spectra. Negative correlations between cortisol concentration and proteins and phospholipids level was observed in the Raman spectra. Both optical techniques are considered to become effective tools for estimating the concentration of cortisol in the plasma.

We nowadays record growing numbers of e-cigarette users. The development of nicotine dependence is a result of many factors, including genetics and personality. In this study we analyzed two polymorphisms—rs1985242 and rs1062613—in the serotonin receptor HTR3A gene in a group of e-cigarette users (n = 135) and controls (n = 106). Personality traits were measured using the NEO Five-Factor Inventory. The comparison of e-cigarette users with the control group indicates that the former showed significantly higher scores on the neuroticism scale and lower scores on the scales of extraversion and conscientiousness of the NEO-FFI. Homozygote variants of rs1985242 were more frequent in the study group. The results of the 2 × 3 factorial ANOVA for e-cigarette users and the control group as well as interaction between the HTR3A rs1985242 variants were found for the NEO-FFI conscientiousness scale. These results allow us to conclude that the combination of psychological factors and genetic data creates a possibility for making more complete models of substance use disorders.

This paper discusses the process of balancing the satellite simulator mounted on the spherical air bearing table. In order to accurately simulate the satellite motion with such a test stand it is necessary to bring the Center Of Mass (COM) of the system as close as possible to the Center Of Rotation (COR) of the air bearing by moving the balancing masses. This calibration process reduces the gravity torque influencing the system movements. A new batch method of determining the COM of the balancing platform is proposed, allowing for its later adjustment. The novelty of the method comes from the idea that the freely rotating system model can be divided into rigid part for which the center of mass is constant, and the balancing masses constituting the variable influence on the COM. Advantage of this approach is the fact, that while gathering data for the batch calibration counterweights can be actuated in a known way, which turns out to greatly improve the estimation precision. Potential disadvantage is, that estimate of the masses and paths of movement of the counterweights is required, which in practice constitutes additional sources of error. Sensitivity analysis is performed to asses the viability of this trade-of considering the inaccuracies in the balance masses paths, as well as sensor noises and misalignment.

A deeper insight into the mechanisms responsible for athlete performance that may serve as specific and detailed training indicators is still desired, because conventionally used biomarkers provide limited information about the adaptive processes that occur during exercise. The objective of our study was to assess insulin-like growth factor 1 receptors (IGF1R) gene expression and evaluate plasma concentration of selected microRNAs (miRNAs) during a 10-week training period (sampling times: week 1, 4, 7, and 10) in a group of 12 professional female volleyball players. Circulating miRNAs (miR-223, miR-320a, and miR-486) with established concentration in plasma and documented association with the IGF1 signaling pathway, which is involved in muscle development and recovery, were tested. The levels of analyzed miRNAs, tested by one-way ANOVA, were significantly different between four training periods during a 10-week training cycle (miR-223 p < 0.0001, miR-320a p = 0.00021, miR-486 p = 0.0037, respectively). The levels of IGF1R also appeared to be different (p = 0.00092), and their expression showed a trend to increase between the first and third periods. In the fourth period, the expression decreased, although it was higher compared with the baseline. Correlations between concentration levels of miR-223 and miR-320a (rs = 0.54, p < 0.001), as well as between miR-320a and miR-486 (rs = 0.73, p < 0.001) were also found. In the fourth period, a negative correlation between miR-223 plasma level and leucocyte IGF1R expression was found (rs = −0.63, p = 0.028). Multiple linear regression analysis showed that miR-320a (p = 0.024) and creatine kinase (p = 0.028) had the greatest impact on the expression levels of the IGF1R gene. Future studies are required to define whether these miRNAs, especially miR-320a, as well as IGF1R expression could be useful biomarkers of physiological changes during exercise and to discover their detailed biological roles in mode-specific exercise training adaptations of professional athletes.

In each touristic city waste management system has to overcome the impact of visitors. Dubrovnik, famous as popular touristic destination, particularly notices tourists visiting city. Therefore potential impact of waste management in touristic cities, such as Dubrovnik, is presented. The paper includes estimation of yearly waste production by inhabitants and tourists visiting those city. Waste digestion is a method for biogas production. On the basis of the preceding estimation combined-cycle installation generating heat and electricity is proposed. The model combines Brayton cycle with low temperature Kalina model based on Rankine cycle. Literature analysis presents state of the art in this field. The simulation is prepared in Cycle-Tempo. Numerical analyses lead to technical issues, which have to be taken into consideration during waste utilization with such installation. Thus benefits and threats are discussed. The presented analysis assesses the maximal electric gain, which subsequently should consider waste preparation and purification

Glioblastoma, also called glioblastoma multiforme (GBM), is a particularly malignant form of primary brain tumor. This cancer accounts for 12–15% of all brain tumors. Despite the advances in neurosurgery, radio and chemotherapy the average survival rate is only 12.1–16.6 months. This is due not only to the late diagnosis of the disease, but also to ineffective treatment methods which result from the still low knowledge about the causes of glioblastoma development. Therefore, it is very important to look for new diagnostic methods of detection of the smallest features of cancer. Raman and infrared spectroscopy (FTIR) can be such methods. In this paper we discuss the chemical composition of sample glioblastoma brain tissues and marginal brain tissues using these two spectroscopy methods. Raman and FTIR spectra of cancer brain tissues showed that the highest differences in the chemical composition, compared to the control brain tissue, occur in the areas corresponding to lipids, collagen and proteins. Moreover, Raman spectroscopy also showed significant changes in the cancer tissues in the phosphatidylcholine and sphingomyelin. Interestingly, FTIR spectra after Kramers-Kronig transformations showed signals only for three peaks which corresponded to the vibrations of lipid function groups. Adjustment of the Lorenz function for these three peaks showed that only in the case of cancerous tissues the number of matching lines is different, compared to the control and marginal tissues. Therefore, we assume that lipids could be a spectroscopic marker for brain tumor. Furthermore, principal component analysis (PCA) showed that chemical changes seen between cancer and control tissues are significant and it is possible to differentiate the infected tissue from the healthy one. Interestingly, the PCA analysis also showed that adjacent brain tissues have different chemical composition than the control tissues.

Waste management is a crucial process to keep the environment in wholesome conditions. The environmental impact of solid waste and wastewater is reduced through construction of appropriate disposal installations. The objective of wastewater treatment in biological reactors is to control the process of biomaterial growth by aerating the sewage content. The process is complex, as depending on a plenty of parameters. In the last decades an effective numerical model, called the Activated Sludge Model (ASM), has been proposed for describing the biological process. The ASM is implemented in the Benchmark Simulation Model (BSM) that simulates the whole wastewater treatment process. The most important parameters in ASM are the kinetic and stoichiometric coefficients. The former describes rate-concentration dependence. The latter characterises the relationship between the components of chemical reactions taking place in the cleaning process. Above parameters are determined by on-site calibration and their importance is relevant during the development of numeric models. This paper aims to examine the influence of kinetic and stoichiometric parameters on the wastewater treatment process of a plant in Płaszów, Kraków. The analysis is carried out by a sample-based numerical procedure. It highlights the ASM parameters playing a major role in the treatment process. Results obtained from the analysis are important for future validation and optimisation processes.

Today, there is a complete lack of appropriate regulatory provisions governing the fire safety assessment of bridges, in particular, specifying the load criteria under fire exposure, with which primary and secondary load-bearing elements should comply. Similarly, the new harmonized bridge structure design standards do not put forward in their decisions any substantive provisions which would allow conducting this type of analysis. In accordance with the preamble of the latest set of European structural design standards “The Member States of the EU and EFTA recognize that Eurocodes serve as reference documents for the following purposes: – as a means to prove compliance of building and civil engineering works with the essential requirements of Council Directive 89/106/EEC, particularly Essential Requirement No 1 (Mechanical resistance and stability), and Essential Requirement No 2 (Safety in case of fire);[…]”. In fact, it appears that, with regard to Essential Requirement No 2 this clause - in particular in relation to objects other than buildings - is dead and does not translate to any specific guidelines, which would allow the achievement of the objective. The authors shall carry out a thorough analysis of legislation and design standards in force in the EU Economic Area, indicating their flaws and lack of coherence. They shall provide a proposal for how to carry out a load assessment of bridge structure elements under fire exposure and specify criteria which, in their opinion, strongly justify the need to conduct such analyses.

The purpose of this paper is to present procedures and methods for assessing fire resistance of steel-beam floors with the joists hidden within the thickness of the slab. These technologies, popular many years ago, are currently experiencing their renaissance, both in contemporarily designed buildings and the existing ones, subjected to comprehensive redevelopment, refurbishment or modernization. Due to their simplicity and ease of execution, these floors are just perfect as technology ideal for repairs or alterations of buildings under use or in the case of need of complete replacement of existing floors with new ones resulting e.g. from the change in use and function of the building, resizing of loads or degradation of existing structural members in historic buildings. These arguments justify the need to raise the subject of proper safety assessment of these floors in relation to the regulations and requirements of laws applicable in the European Union and pursuant to provisions of the latest codes for structural design. The author proposes to use procedures taken from Eurocode 3, Parts 1-2, to determine the fire resistance of this type of floors, while pointing out to the problem of significant discrepancies in final results, depending on the chosen path/variant of procedure and assumptions made. The results of computational example presented in the study shows that contrary to a popular belief, the use of standard fire model does not always lead to conservative estimates. This shows the need for a special insight when evaluating fire conditions and the necessity to treat each design case on an individual basis and with considerable attention. In the article summary, the author formulates a number of practical applications and conclusions.

There is no clear evidence that vitamin D effectively improves physical capacity in high-level athletes. The aim of this study was to confirm that vitamin D supplementation of soccer players during eight-week high-intensity training would have a significant effect on their aerobic capacity. The subjects were divided into two groups: the experimental one that was supplemented with vitamin D (SG, n = 20), and the placebo group (PG, n = 16), not supplemented with vitamin D. All the players were subjected to the same soccer training described as High-Intensity Interval Training (HIIT). The data of the vitamin D level, PWC170, lactate threshold (LT) were collected just before and after the intervention. A significant increase in vitamin D concentration (119%) was observed in the supplemented group, while the non-supplemented group showed a decrease of 8.4%. The studied subjects improved VO2max results by 20% in the SG, and by 13% in the PG. The improvement in velocity at the LT was similar in both groups. Results of this study show that vitamin D can have a positive, though moderate, effect on aerobic performance in players subjected to high-intensity training in the form of small-sided games for 8 weeks.

Objective: To identify the difference in infraspinatus, posterior deltoid, and teres minor muscle fatigability between the dominant and non-dominant side in elite volleyball players and to examine the differences between three sEMG signal processing methods used in assessment of shoulder muscle imbalance due to fatigue in volleyball players. Methods: In 18 male volleyball players (21-26 years; 186.6 ± 8.4 cm; 85.7 ± 9.8 kg) with no previous shoulder injury the bioelectrical activity of the right and left infraspinatus, posterior deltoid, and teres minor muscles was measured during 60 seconds of isometric contraction in prone position with the shoulder in external rotation. Fatigue related changes as mean frequency shift were calculated from the RAW sEMG signal using 3 processing methods: FFT (Fast Fourier Transform), STFT (Short Time Fourier Transform) and CWT (Morlet Continues Wavelet Transform). Results: There were no statistically significant differences (p>0.05) in the values of the mean frequency slope, intercept and difference between dominant and non-dominant sides in all the evaluated muscles. There were no significant differences between FFT and STFT sEMG signal processing methods in mean frequency slope, intercept values and difference. The sEMG signal processing using CWT showed the significantly higher values of mean frequency slope for infraspinatus and teres minor muscles. Significantly lower values of mean frequency intercept were observed for the infraspinatus, posterior deltoid and the teres minor muscles. There were no significant differences observed in mean frequency difference for all the evaluated muscles. Conclusions: In elite volleyball players without previous shoulder injury, the fatigue indices in muscles of the shoulder region were similar on both the dominant and non-dominant sides. Therefore, we have hypothesized that asymmetric shoulder loading during volleyball training should not be considered as an obvious factor increasing the risk of shoulder injury. Muscle fatigue indices measured by sEMG may be a sensitive and objective method of evaluation, but may reach different values depending on the used signal processing method. Consequently, the clinical interpretation and any comparison between different measurements, without knowledge of how those values were calculated, may be misleading and be the reason for misdiagnosis.

The purpose of this study was to examine the association of the BstUI RFLP C/T (rs 12722) and DpnII RFLP C/T (rs 13946) COL5A1 polymorphisms, individually and as haplotypes, with anterior cruciate ligament ruptures in recreational skiers. Subjects were 138 male recreational skiers with surgically diagnosed primary anterior cruciate ligament ruptures. The control group consisted of 183 apparently healthy male recreational skiers, who were without any self-reported history of ligament or tendon injury. DNA was extracted from buccal cells donated by the subjects and genotyping was carried out using real-time PCR. The genotype distributions for both polymorphisms met Hardy- Weinberg expectations in both groups. There were no significant differences in genotype distribution of allele frequencies of COL5A1 BstUI RFLP C/T and COL5A1 DpnII RFLP C/T polymorphisms between the ACL rupture and control groups. The T-T (BstUI RFLP T, DpnII RFLP T) haplotype was the most common (55.6%). The haplotype T-C was not present in any of the subjects. There was an underrepresentation tendency of the C-T haplotype in the study group compared to controls under recessive mode of inheritance. Higher frequency of the COL5A1 BstUI RFLP C/T and COL5A1DpnII RFLP C/T polymorphisms haplotype is associated with reduced risk of anterior cruciate ligament injury in a group of apparently healthy male recreational skiers.

Although various intrinsic and extrinsic risk factors for anterior cruciate ligament (ACL) rupture have been identified, the exact aetiology of the injury is not yet fully understood. Type III collagen is an important factor in the repair of connective tissue, and certain gene polymorphisms may impair the tensile strength. The aim of this study was to examine the association of the COL3A1 rs1800255 polymorphism with ACL rupture in Polish male recreational skiers. A total of 321 male Polish recreational skiers were recruited for this study; 138 had surgically diagnosed primary ACL ruptures (ACL-injured group) and 183 were apparently healthy male skiers (control group – CON) who had no self-reported history of ligament or tendon injury. Both groups had a comparable level of exposure to ACL injury. Genomic DNA was extracted from the oral epithelial cells. All samples were genotyped on a real-time polymerase chain reaction instrument. The genotype distribution in the ACL-injured group was significantly different than in CON (respectively: AA=10.1 vs 2.2%, AG=22.5 vs 36.1, GG=67.4 vs 61.8%; p=0.0087). The AA vs AG+GG genotype of COL3A1 (odds ratio (OR) = 5.05; 95% confidence interval (CI), 1.62-15.71, p = 0.003) was significantly overrepresented in the ACL-injured group compared with CON. The frequency of the A allele was higher in the ACL-injured group (21.4%) compared with CON (20.2%), but the difference was not statistically significant (p=0.72). This study revealed an association between the COL3A1 rs1800255 polymorphism and ACL ruptures in Polish skiers.

The purpose of this article is to present procedures and methodsfor assessing fire resistance of steel-beam floors with thejoists hidden within the thickness of the slab. These technologiesare currently experiencing their renaissance, both in contemporarilydesigned buildings and the existing ones, subjectedto comprehensive redevelopment, refurbishment or modernization.Due to their simplicity and ease of execution, these floorsare just perfect as technology ideal for repairs or alterations ofbuildings under use or in the case of need of complete replacementof existing floors with new ones. These arguments justifythe need to raise the subject of proper safety assessment of thesefloors in relation to the regulations and requirements of lawsapplicable in the EU and pursuant to provisions of the latestcodes for structural design. A significant part of the study consistsof a suggestive computational example, which is a sort ofguide, in which the author, by making detailed step-by-step calculationsproduces a finished pattern of procedure, intended formultiple use. The suggested method of procedure can be successfullyused in the assessment of the fire resistance of floorstructures with similar technical features. The computationalexample presented in the study shows that contrary to a popularbelief, the use of standard fire model does not always leadto conservative estimates. In the article summary, the authorformulates a number of practical applications and conclusions.

We hypothesized that the ACE ID / ACTN3 R577X genotype combination was associated with sprint and endurance performance. Therefore, the purpose of the present study was to determine the interaction between both ACE ID and ACTN3 R577X polymorphisms and sprint and endurance performance in swimmers. Genomic DNA was extracted from oral epithelial cells using GenElute Mammalian Genomic DNA Miniprep Kit (Sigma, Germany). All samples were genotyped using a real-time poly- merase chain reaction. The ACE I/D and the ACTN3 R577X genotype frequencies met Hardy-Weinberg expectations in both swimmers and controls. When the two swimmer groups, long distance swimmers (LDS) and short distance swimmers (SDS), were compared with control subjects in a single test, a significant association was found only for the ACE polymorphism, but not for ACTN3. Additionally, four ACE/ACTN3 combined genotypes (ID/RX, ID/XX, II/RX and II/XX) were statistically significant for the LDS versus Control comparison, but none for the SDS versus Control comparison. The ACE I/D and the ACTN3 R577X polymorphisms did not show any association with sprint swimming, taken individually or in combination. In spite of numerous previous reports of associations with athletic status or sprint performance in other sports, the ACTN3 R577X polymorphism, in contrast to ACE I/D, was not significantly associated with elite swimming status when considered individually. However, the combined analysis of the two loci suggests that the co-occurrence of the ACE I and ACTN3 X alleles may be beneficial to swimmers who compete in long distance races

The GSTP1 c.313A>G polymorphism is a candidate to explain some of the individual differences in cardiorespiratory fitness phenotypes’ responses to aerobic exercise training. We aim to explore the association between the GSTP1 c.313A>G polymorphism and the response to low-high impact aerobic exercise training. Sixty-six Polish Caucasian women were genotyped for the GSTP1 c.313A>G polymorphism; 62 of them completed 12-week aerobic (50-75% HR max ) exercise training and were measured for selected somatic features (body mass and BMI) and cardiorespiratory fitness indices – maximal oxygen uptake (VO 2max , maximum heart rate (HR max ), maximum ventilation (V Emax ) and anaerobic threshold (AT) – before and after the training period. Two-factor analysis of variance revealed a main training effect for body mass reduction (p=0.007) and BMI reduction (p=0.013), improvements of absolute and relative VO 2max (both pG interaction was found only for FFM (p=0.042), absolute and relative VO 2max (p=0.029 and p=0.026), and V Emax (p=0.005). As the result of training, significantly greater improvements in VO 2max , V Emax and FFM were gained by the GG+GA group compared to the AA genotype group. The results support the hypothesis that heterogeneity in individual response to training stimuli is at least in part determined by genetics, and GSTP1 c.313A>G may be considered as one (of what appear to be many) target polymorphisms to influence these changes.